1. Field of the Invention
The present invention relates to the preparation of itaconic acid by fermentation, and, more especially, via microbial fermentation of particular nutrient media.
2. Description of the Prior Art
The production of organic acids by fermentation of sugars in the presence of a suitable microorganism is universally known to this art. Typical acids of such fermentations include, in particular, acetic acid, lactic acid, citric acid, fumaric acid and, more especially, itaconic acid.
Itaconic acid is a dicarboxylic acid having the following structural formula: ##STR1##
By reason of its site of ethylenic unsaturation, itaconic acid esters polymerize very readily and are thus widely used in the detergent and synthetic plastics industries and in the preparation of adhesives.
Traditionally, the production of itaconic acid is carried out by fermentation. Various varieties of the genus Aspergillus, and more especially those of Aspergillus terreus and Aspergillus itaconicus, are used for producing itaconic acid via fermentation of carbohydrates.
The carbohydrates most typically used include mono- and disaccharides, such as glucose, sucrose and fructose and starches, as they exist in a form which is assimilable by the microorganism, and molasses.
Indeed, in traditional fermentations, from an economic standpoint, the selection of the hydrocarbon substrate should be based both on its cost, on its availability and on its capacity to provide high yields.
Thus, in order to economically optimize the processes for preparing itaconic acid, it is necessary to select a hydrocarbon source that simultaneously satisfies the aforesaid three requirements.